I have 2 cheap 3d printers, you can get a functional printer for under $200, but you also are buying a new hobby at that price. If you have a little more money than time, the Prusa printers look like a great deal. Having worked with 3d printing for a while some of the new features on the i3 mk3 would be very nice, the coated steel bed so you don't have to mess with tape or glue to get the plastic to stick is a big improvement. the sensors for recovery on power failure or filament issues is also huge.
As for embedding metal parts in the plastic I'm planning on trying that this week, so this is still theory for me. The inserted part needs to be no higher than the layer just printed, there can be some gaps or holes, the filament will bridge over small open spaces. The plastic can only bond to the top of the insert, it's already cooled off everywhere else it touches it, it might be possible to glue the insert in though.